مجله تولید و فرآوری محصولات زراعی و باغی
سال هفتم شماره 4 (زمستان 1396)

Safflower (Carthamustinctorius L.) is one of the oldest domesticated crops, mainly grown as an oilseed in the arid and semiarid regions of the world. This study was conducted to investigate the Cardinal temperatures and to identify the effects of occurrence of drought stress in maternal environment on seed germination aspects of some Carthamus species according to a completely randomized design in 2014. To accomplish this, seeds of 13 genotypes from C. tinctorius, C. palaestinus, C. oxyacanthus, C. glaucus and C. lanatus were used which had been harvested from plants grown at normal and drought stress conditions. Seeds were subjected to 9 fixed temperatures (5, 10, 15, 20, 25, 30, 35, 40 and 45°C) for germination in the growth chamber according to a factorial experiment. Results showed that the effects of genotype, species, temperature, pretreatment drought stress and some of their interactions were significant for certain germination characteristics at 0.05% probability level. Significant reductions occurred in the germination rate of seeds at temperatures below 10°C and above 30°C. Although there were significant differences in percent of seed germination among species, seeds harvested from drought stressed plants were not significantly different from the ones harvested from non-stressed plants in terms of cardinal temperatures. Hence, it is more likely that cardinal temperatures will not cause difficulties in the case of inter-specific breeding programs for drought tolerant safflower cultivar development.

Plant growth regulators may leave positive effects on different plants. A factorial experiment using RCBD was conducted to study the impact of brassinosteroied (Br) and ethephon on growth and development of cantaloupe (Shahpasandi) in 2014, in Kerman University Research Station, Kerman, Iran. Three levels of Br (0, 0.5 and 0.75 mM) as seed soaking and two levels of ethphon (0 and 250 mg/l) as foliar spray at 4- and 20-leaf stage were used. Br was effective on all examined traits with the exception of leaf relative water content, leaf dry weight and fruit quality. Br at 0.75 mM was most effective, producing the highest amount of leaf area (200 cm2/plant), fruit weight per plant (2.9 kg) and total fruit yield per hectare (50 tons). Relative to control, Br increased fruit reducing sugars concentration, leaf soluble protein contents, leaf chlorophyll concentration, and fruit number by 50%, 21%, 23.8% and 42%, respectively. Ethephon treatment applied at 20-leaf stage increased fruit reducing sugar concentration, leaf chlorophyll, and fruit number by 52%, 19.1% and 14.8%, respectively. Interactive effects of the two factors was significant for chlorophyll a and carotenoids concentrations. However, Br at 0.75 mM level and ethephon applied at 20-leaf stage were more effective than other treatments but Br at 0.75 mM increased the fruit yield by 41%.

In order to investige the effect of nitrogen and Azospirillum biological fertilizers on the growth and yield of an Iranian bread wheat (Roshan cultivar) this study was carried out using a factorial experiment based on a randomized complete block design with three replications at a field in Jozan region, Isfahan, Iran in 2013. The experimental factors included Azospirillum brasilense bacterium at two levels (inoculated or non-inoculated), and nitrogen fertilizer at five levels (0, 50, 100, 150 and 200 kg ha-1 of N). The application of Azospirillum increased grain yield and agronomic characteristics including the number of spikes m-2, 100-seed weight, protein content and SPAD number. The interaction effects of the two factors were also significant on grain yield, number of spikes m-2, 100-seed weight and grain protein content (P≤0.05) and plant height and SPAD number (P≤0.01). The greatest grain yield (4607 kg ha-1), grain protein content (12.71%) and SPAD number (53.33) obtained from the plants treated with Azospirillum and N-fertilizer at 50 kg ha-1. The highest number of spikes per m2 (471.42) and 100-seed weight (48.4 g) were produced by Azospirillum inoculation and N-fertilizer at the rate of 100 kg ha-1. Overall, the inoculation with Azospirillum bacteria and the application of 50 kg ha-1 N seemed suitable to achieve maximum grain yield, to reduce the adverse environmental impacts and to maintain the N-fertilizer. Albeit, further recommendation warrants future studies.

Apple fruit color is determined by the amount of pigments in its peel which is directly affected by sunlight. A method for improving apple fruit color is bagging. In present study, the effect of bagging and its optimum removing time was investigated on the amount of peel pigments and other fruit quantitative and qualitative characteristics for Fuji and Granny Smith apples. The experimental treatments were, no bag (control), debagging 7 and 14 days before harvest, and keeping the bag until harvest time. At the end of experiment, the amount of pigments, total soluble solids, titratable acidity, pulp phenol, peel phenol, antioxidants percentage, fruit weight and volume were measured. The results showed that in debagging 7 and 14 days before harvest treatments, the amount of anthocyanin and soluble solids statistically increased as compared with control; however other measured characteristics were significantly reduced in both apple cultivars. The maximum amount of fruit anthocyanin (60.96 mg/g fresh weight) belonged to Fuji cultivar in 14 days treatment and the least amount of fruit anthocyanin (1.64 mg/g fresh weight) belonged to Granny Smith cultivar in zero-day treatment. The highest amount of fruit chlorophyll a (5.09µgr/lit) was observed in control fruit and the lowest amount of fruit chlorophyll a (3.94 µgr/lit) was observed in 14 days treatment. The decrease of chlorophyll amount is a positive characteristic for the Fuji and a negative one for Granny Smith. Therefore, bagging and 14 days before harvest debagging treatment increased the amount of anthocyanin and decreased chlorophyll which resulted in Fuji cultivar better coloring and reducing the green color quality of Granny Smith cultivar.

In order to study the effect of planting date and application of chemical and biological fertilizers on yield and yield components of peanut, an experiment was conducted in split plot based on a randomized complete block design with three replications at the Research Station of Bu-Ali Sina University, Hamedan, Iran, in 2012. Three planting dates, including May 22, May 31 and June10, as main plot, and four fertilizer treatments including 50% of nitrogen chemical fertilizer nitrogen biofertilizer complete phosphorus chemical fertilizer, 50% of phosphorus chemical fertilizer phosphorus biofertilizer complete nitrogen chemical fertilizer, 50% of nitrogen chemical fertilizer 50% of phosphorus chemical fertilizer nitrogen and phosphorus biofertilizers, 100% chemical fertilizer, as subplot, were used. Results showed that interaction effect between planting date and biofertilizers was significant for number of pods per plant, pod length, seed yield and biological yield, harvest index at the 1% level, and for 1000-seed weight at the 5% level. The highest grain yield was obtained on the first planting date (May 22) with using complete chemical fertilizer (1054 kg/h) and then with the application of both biofertilizers and 50% of nitrogen and phosphorus chemical fertilizers (965 kg/h). Application of nitrogen and phosphorus biofertilizers alone brought about47.50 and 24.9% decreases in grain yield, compared to complete chemical fertilizer, respectively. Therefore, it seems that concomitant application of nitrogen and phosphorus biofertilizers (i.e. 50% nitrogen and phosphorus chemical fertilizer) at May 22 planting date is suitable for sowing peanut in Hamedan conditions.

To study the effects of delayed irrigation on growth and ratoon of millet (Pennisetum americanum cv. Nutrifeed) in the first harvest and sorghum (Sorghum bicolor cv. Speedfeed), a field experiment was conducted as split plot based on a randomized complete blocks design with three replications in Faculty of Agriculture, Vali-e-Asr University of Rafsanjan, Iran, at summer 2014. Factors consisted of irrigation regime at three levels, including irrigation after 80 (control), 120 and 160 mm evaporation from a Class A evaporation pan as main plots, crop species at two levels, including Nutrifeed (millet) and Speedfeed (sorghum) as subplots and harvest number ( at two levels) as sub-sub plots. At regrowth, all treatments were irrigated as control regime (80 mm evaporation). At 1st harvest, delayed irrigation decreased leaf photosynthetic pigments contents, LAI, SLA, LWR, leaf and stem dry weight and forage yield and increased proline, sucrose and leaf soluble sugars contents at both species. Similar effects of delayed irrigation were observed at regrowth. The highest forage yield belonged to normal irrigation of Speedfeed (9376 kg/ha), however, Nutrifeed showed a better performance at regrowth (4250 and 3816 kg/ha of forage, respectively). Nutrifeed had a better forage quality, owing to a higher leafiness index at both harvests (46.7% and 45.0%, respectively).

Drought stress is one of the major abiotic stresses that limits rice productivity in the world. In this study 83 diverse rice genotypes were evaluated under reproductive-stage drought stress and non-stress conditions in a completely randomized design with three replications. Eleven well known stress tolerance and susceptibility indices were calculated based on the grain yield under stress and non-stress conditions. Also rank mean (RM) indices were calculated based on the ranks of genotypes for the former calculated indices. The highest seed yield under non-stress condition belonged to the genotypes Sangjo, Zenith, IR70445-146-3-3, Norin 22 and Ghasroldashti. Under stress condition, however, IR83750-131-1, IR74718-24-2-3, Sepidrood, TETEP and IR71739-24-3-5 genotypes showed the highest seed yield. STI, GMP, MRP and REI indices with positive and significant correlations with grain yield in stress and non-stress conditions were found to be the most suitable indices for selection of drought tolerant rice genotypes. According to these indices, IR83750-131-1, Sangjo, Sepidrood, Zenith and IR58 genotypes showed the highest ranks and had a higher tolerance to drought stress. Based on RM index, IR83750-131-1, IR74718-24-2-3, Sepidrod, TETEP and IR74720-13-1-2 obtained the highest ranks. Cluster analysis grouped the most drought tolerant genotypes in the second cluster.

Bromus danthoniae Trin. is an annual grass species that is well adapted to harsh climates and could be considered as an important genetic resources for tolerance to environmental stresses such as salinity. In this study, 24 genotypes collected from Ilam, Kurdistan, Kermanshah (non-saline areas) and West Azerbaijan (saline area: shores of Uremia Salt Lake) provinces of Iran were investigated at the germination stage under salt treatments with concentrations of 0, 60, 120, 180, 240 and 300 mM sodium chloride. Germination percentage, germination rate index, seed vigor, root length, shoot length and seedling fresh and dry weights were measured. In addition, the relationship between the percentage of germination in 300 mM sodium chloride and the survival rate (%) after four weeks in 350 mM sodium chloride at the vegetative stage was evaluated. The results of analysis of variance showed that salinity treatments caused significant reductions in all the studied traits. Genotypic variation and the interaction of genotype × salt treatments were also significant. Genotypes USLN3 and KER4 were found to be the most tolerant and sensitive genotypes to salinity stress, with 13% and 98% reduction in germination percentage at 300 mM NaCl, respectively. Cluster analysis divided the genotypes into three groups, with one group containing only tolerant genotypes from Uremia Salt Lake, another one comprising only sensitive genotypes from non-saline regions, and the third one containing genotypes from both regions. The correlation between the germination percentage and the survival rate at the vegetative stage was not significant, indicating that different mechanisms are, perhaps, responsible for salinity tolerance at the germination and vegetative stages in B. danthoniae.

Wheat grain yield reduction occurs in most wheat growing regions of Iran due to post-anthesis water stress. This research was conducted to evaluate yield and yield components of wheat cultivars in normal irrigation and post anthesis irrigation cut-off conditions as a split-plot arrangement based on a randomized complete block design with three replications during 2015-16 in College of Agriculture, Shiraz University, Shiraz, Iran. The main plots included irrigation regimes (normal irrigation until the end of the growth season and irrigation cut-off from flowering to maturity) and subplots composed of 20 bread wheat cultivars. The results showed that irrigation cut-off caused a significant reduction in biological yield (46.4%), grain yield (59%), harvest index (23.7%), number of grains per spike (27.1%) and 1000 grain weight (13.8%). The highest grain yield in normal irrigation (1002 gm-2) and post anthesis irrigation cut-off conditions (485.7 gm-2) was obtained from Danesh cultivar. Among indices, stress tolerance index (STI), mean productivity (MP), and geometric mean productivity (GMP) had positive and significant correlations with grain yield in stress and non-stress conditions. Therefore, it appeared that these indices might be suitable for identification and selection of wheat cultivars that are tolerant to post anthesis irrigation cut-off. In general, the results indicated that Danesh, Sirvan, Baharan, Jones and Symonyda cultivars out–yielded the remaining ones under both stress and non-stress conditions.

The storage life of mushrooms is less than the other vegetables due mainly to high water contents and a porous and thin epidermal structure. This research was aimed at obtaining a suitable compost combination and an optimal condition of maintenance for increase the storage life of button mushroom. The experimental factors consisted of two maintenance temperatures (4°C and 25°C), two types of packages (transparent and covered with foil) and four types of composts (wheat straw and chicken manure, wheat straw and horse manure, rice straw and chicken manure, rice straw and olive bagasse). Attributes such as percent of weight loss, browning area, percent of dry matter, total phenol and antioxidant capacity of stored samples were assessed 7 days after harvest in room temperature and 25 days after harvest in refrigerator temperature. Mushrooms grown in rice straw and olive bagasse compost had the highest dry matter (11.62%), when stored in room temperature. Mushrooms grown in rice straw and olive bagasse compost had the highest antioxidant capacity in both refrigerator and room temperatures when stored in the package covered with foil. According to our results, rice straw and olive bagasse compost is potent to increase the storage life of the button mushroom and merits further studies.